/Engine/Plugins/FX/Niagara/Source/NiagaraEditor/Public/NiagaraParameterMapHistory.h
Record that a pin writes to the parameter map. The pin name is expected to be the namespaced parameter map version of the name. If any aliases are in place, they are removed.
int32 HandleVariableWrite ( int32 ParameterMapIndex, const [FInputPin](API\Plugins\NiagaraEditor\TNiagaraParameterMapHistoryBuild-\FInputPin) * InPin )